ACPI cpu throttling

Hi,

I have an HP zd7145eu laptop with FC 2 (and current patched installed) the laptop has a P4 3Ghz HT processor (800mhz fsb model). The only problem is that the /proc/acpi/processor/CPU0/throttling reports that the it is currently running in T1 mode (12% reduction in processor performance.?) and no matter what i try i cannot get this to change. I am currently running a custom kernel but i have tested with the stock SMP kernel but i am getting the same issue.

If anyone can give me some pointers it would be a great help as i've spent a couple of days looking for a solution with no luck.

tia

Steve